It may be very difficult for the doctor to distinguish between eczema and psoriasis. Other forms of eczema such as atopic dermatitis and nummular eczema should be considered in the differential diagnosis. Fungal infections can occur on both the back of the hands and palms.
Psoriasis of the palms. Irritant and allergic contact dermatitis can have exactly the same pattern of inflammation.
Atopic dermatitis on the back of the hand of an adult.
Nummular eczema appears with round patches. The cause of this common form of eczema is unknown. It is frequently misdiagnosed as psoriasis or ringworm.
Tinea (ringworm) on the back of the hand. The nails may also be infected with fungus.